Reporting a Jew to Non-Jewish Authorities

וַיֵּצֵא֙ בַּיּ֣וֹם הַשֵּׁנִ֔י וְהִנֵּ֛ה שְׁנֵֽי־אֲנָשִׁ֥ים עִבְרִ֖ים נִצִּ֑ים וַיֹּ֙אמֶר֙ לָֽרָשָׁ֔ע לָ֥מָּה תַכֶּ֖ה רֵעֶֽךָ׃ וַ֠יֹּאמֶר מִ֣י שָֽׂמְךָ֞ לְאִ֨ישׁ שַׂ֤ר וְשֹׁפֵט֙ עָלֵ֔ינוּ הַלְהָרְגֵ֙נִי֙ אַתָּ֣ה אֹמֵ֔ר כַּאֲשֶׁ֥ר הָרַ֖גְתָּ אֶת־הַמִּצְרִ֑י וַיִּירָ֤א מֹשֶׁה֙ וַיֹּאמַ֔ר אָכֵ֖ן נוֹדַ֥ע הַדָּבָֽר׃ וַיִּשְׁמַ֤ע פַּרְעֹה֙ אֶת־הַדָּבָ֣ר הַזֶּ֔ה וַיְבַקֵּ֖שׁ לַהֲרֹ֣ג אֶת־מֹשֶׁ֑ה וַיִּבְרַ֤ח מֹשֶׁה֙ מִפְּנֵ֣י פַרְעֹ֔ה וַיֵּ֥שֶׁב בְּאֶֽרֶץ־מִדְיָ֖ן וַיֵּ֥שֶׁב עַֽל־הַבְּאֵֽר׃

Exodus 2:13-15

When he went out the next day, he found two Hebrews fighting; so he said to the offender, “Why do you strike your fellow?” He retorted, “Who made you chief and ruler over us? Do you mean to kill me as you killed the Egyptian?” Moses was frightened, and thought: Then the matter is known! When Pharaoh learned of the matter, he sought to kill Moses; but Moses fled from Pharaoh. He arrived in the land of Midian, and sat down beside a well.

שמות רבה א׳:ל״א

וַיִּשְׁמַע פַּרְעֹה, שֶׁעָמְדוּ דָּתָן וַאֲבִירָם וְהִלְשִׁינוּ עָלָיו. וַיְבַקֵּשׁ לַהֲרֹג אֶת משֶׁה, שָׁלַח פַּרְעֹה וְהֵבִיאוּ סַיִּף שֶׁאֵין כְּמוֹתָהּ, וּנְתָנוֹ עֶשֶׂר פְּעָמִים עַל צַוָּארוֹ וְנַעֲשָׂה צַוָּארוֹ שֶׁל משֶׁה כְּעַמּוּד הַשֵּׁן וְלֹא הִזִּיקַתּוּ, שֶׁנֶּאֱמַר (שיר השירים ז, ה): צַוָּארֵךְ כְּמִגְדַּל הַשֵּׁן.

Shemot Rabbah 1:31

When Pharaoh learned of the matter for Datan and Aviram had reported Moshe's actions. Pharaoh wanted to kill Moshe, so he requested a sword like none other. They struck his neck with it ten times, but Moshe's neck had become hard as a pillar and was not injured.

משנה תורה, הלכות חובל ומזיק ח׳:ט׳-י׳

אָסוּר לִמְסֹר הָאָדָם בְּיַד עַכּוּ''ם בֵּין בְּגוּפוֹ בֵּין בְּמָמוֹנוֹ. וַאֲפִלּוּ הָיָה רָשָׁע וּבַעַל עֲבֵרוֹת וַאֲפִלּוּ הָיָה מֵצֵר לוֹ וּמְצַעֲרוֹ. וְכָל הַמּוֹסְרוֹ בְּיַד עַכּוּ''ם בֵּין בְּגוּפוֹ בֵּין בְּמָמוֹנוֹ אֵין לוֹ חֵלֶק לָעוֹלָם הַבָּא: מֻתָּר לַהֲרֹג הַמּוֹסֵר בְּכָל מָקוֹם וַאֲפִלּוּ בַּזְּמַן הַזֶּה שֶׁאֵין דָּנִין דִּינֵי נְפָשׁוֹת. וּמֻתָּר לְהָרְגוֹ קֹדֶם שֶׁיִּמְסֹר אֶלָּא כְּשֶׁאָמַר הֲרֵינִי מוֹסֵר פְּלוֹנִי בְּגוּפוֹ אוֹ בְּמָמוֹנוֹ. וַאֲפִלּוּ מָמוֹן קַל הִתִּיר עַצְמוֹ לְמִיתָה. וּמַתְרִין לוֹ וְאוֹמְרִין לוֹ אַל תִּמְסֹר. אִם הֵעֵז פָּנָיו וְאָמַר לֹא כִּי אֶלָּא אֶמְסְרֶנּוּ מִצְוָה לְהָרְגוֹ וְכָל הַקּוֹדֵם לְהָרְגוֹ זָכָה:

Mishneh Torah, One Who Injures a Person or Property 8:9-10

It is forbidden to turn a Jew over into the hands of a heathen, whether physically or financially, even if he happens to be wicked and sinful, and even if he is the cause of one's distress and pain. Anyone who hands a Jew over into the hands of heathen, whether physically or financially, has no share in the world to come. An informer may be slain anywhere, even at the present time when Jewish courts do not try capital cases. It is permissible to slay him before he has informed. As soon as he says that he is about to inform against an individual or his property, even a small amount of money, he has surrendered himself to death [as an outlaw]. He must be warned and told: "Do not inform." If he has acted impudently, replying: "Not so, I will inform against him," it is a religious duty to slay him ; whoever hastens to kill him attains merit.

From: Informing on Others for Violating American Law: A Jewish Law View

by Rabbi Michael J. Broyde - https://www.jlaw.com/Articles/mesiralaw2.html

A. The View of Rabbi Eliezer Yehuda Waldenberg: No Prohibition to Inform when Government is Just

There is a difference between primitive and enlightened governments as is noted by the Aruch Hashulchan where it states that "every issue related to informing found in the Talmud and Halacha deals with those far away places where no one was secure in his money or body because of the bandits and pirates, even those who had authority, as we know nowadays in places like Africa...which is not the case here in Europe." (The author of the Aruch Hashulchan, R' Yechiel Michel Epstein, lived in Lithuania in the late 1800's). Assuming one lives in a just society, they may inform the authorities.

B. The View of Rabbi Ezra Batzri: There Are No Just Legal Systems and No Just Prisons
Rabbi Batzri posits that even when the external justice system seems to work, nonetheless the executive and judicial systems are so deeply fraught with exceptions, and extra-judicial misconduct, and coerced confessions, that one must assume injustice will occur and thus informing on a fellow Jew remains generally prohibited, with two exceptions:

Exception #1 - when the person being informed upon is violent, for the welfare of the community, they should be informed upon.

Exception #2 - when the violation would not bring about any dependence on the executive or judicial systems, I.e. a parking violation, they may be informed upon.

C. The View of Rabbi Feinstein : It Depends on the Type of Crime

If the approach of Rabbi Feinstein is correct, one divides cases of informing into three types of categories:

Category #1 - when the person being informed upon is an individual who is violent, or threatens violence, or induces harm to others or endangers the welfare of the community. Such a person may be informed upon, as Jewish law recognizes the need to remove these people from the community.

Category #2 - In cases where the judgement outcome is identical in secular law and Jewish law, Rabbi Feinstein would say that there is no problem of informing, as there is no damage.

Category #3 - In all other cases, informing is prohibited, and is subject to the rules of informing.