Many Christians believe that Jesus, Paul and the rest of the New Testament teaches that God's laws were abolished (done away with) and that they are no longer valid for believers. They reject what they feel is legalism and in its place ultimately decide for themselves what they 'feel' is the right or loving thing to do in a given situation.
Some religious leaders have gone so far as to label people as being involved with legalism if they accept some Old Testament laws (e.g. the Ten Commandments) or principles (e.g. tithing) as applying to them.
There are, however, believers who accept and obey God's laws (e.g. not eating 'unclean' foods, etc.) but do not view or treat them as a way to earn or preserve their salvation. While some may still label such people as being involved in legalism, the Bible does not.
Surprisingly, the last book of the Bible bears witness to the fact that before the return of Jesus there will be those still obeying God's laws. Additionally, it is only those who keep the commandments (who the world will label as practicing legalism), as witnessed to in Revelation, that will be given eternal life.
Then the dragon (representing Satan in the end time) was furious with the woman (the church of God) and went to make war with (and to kill) the rest of her seed (true Christians), who keep the commandments . . . (Revelation 12:17).
Blessed are those who keep His commandments (the ten commandments, including the fourth one), that they may have the right to eat of the tree of life . . . (Revelation 22:14).
Some churches and groups may reject most, if not all, of God's Commandments and replace them with their own set of church sanctioned 'commandments' that must be followed (e.g. no card playing, dancing, drinking alcohol, etc.). Others, however, still may consider them believing in legalism.