keep (your) hands clean - to avoid becoming involved in any activities which are bad or illegal.

The country's leaders must be seen to have clean hands.

• sink or swim
• sink teeth into
• sink teeth into something
• sink to such depths
• sink without trace
• sink your teeth into
• sink your teeth into something
• sin tax
• siphon off
• siphon off something
• sit around on backside
• sit around on your backside
• sit back
• sit back and
• sit back and do something
• sit by
• sit by and
• sit by and do something
• sit idly by
• sit idly by and
• sit idly by and do something
• sit in
• sit in for
• sit in for someone
• sit in judgment