Arranged - no, it shouldn't. (I'll explain in a minute)
Forced - Yes, it should be illegal.
Why shouldn't Arranged Marriage be illegal? Because there is a difference to arranged and forced. Arranged, as long as you have the option to decline - both the male and female - for any reason such as sexuality, having fallen in love with someone else prior to the time the marriage was arranged for, abusive history - no sense in marrying a douche, MASSIVE age difference, underage marriage etc.
Often, culturally, people are betrothed to a person from birth, and they do get to know them - if they don't want to, it should be okay to pull out. IF they don't have the option to pull out - it's forced marriage, and tantamount to rape.
Why do I think this, given I come from a country and culture that arranged marriage is NOT done? Because I understand that there are cultural reasons for this - and they don't just pick the prospective partner in a random fashion - they put thought into it, who would suit their child etc. I have a friend who's sister was married in an arranged marriage - and they are perfectly happy. However, she was arranged as well - but able to choose whether she went with them...and if she didn't - that was fine.
On the original question - errr, arranged marriage isn't taking away the right to freedom of speech - That doesn't make sense.