Chulin6: 2
הַשּׁוֹחֵט וְנִמְצָא טְרֵפָה, וְהַשּׁוֹחֵט לַעֲבוֹדָה זָרָה, וְהַשּׁוֹחֵט חֻלִּין בִּפְנִים וְקָדָשִׁים בַּחוּץ, חַיָּה וָעוֹף הַנִּסְקָלִים — רַבִּי מֵאִיר מְחַיֵּב, וַחֲכָמִים פּוֹטְרִין. הַשּׁוֹחֵט וְנִתְנַבְּלָה בְיָדוֹ, הַנּוֹחֵר וְהַמְעַקֵּר, פָּטוּר מִלְּכַסּוֹת.
[If] one slaughters and it is found [to be] a treifah, or [if] one slaughters for idolatry, or [if] one slaughters unconsecrated animals inside [the Temple Courtyard] or consecrated ones outside, [or if one slaughters] a beast or fowl sentenced to stoning — R’ Meir declares him obligated [to cover the blood], but the Sages exempt [him]. [If] he slaughtered [it] and it became a neveilah through his hand, [or if] he pierced its nostrils or tore out the throat organs, he is exempt from covering [the blood].